KR100287403B1 - How to prevent malfunction of CD player - Google Patents

Abstract

According to the present invention, the CD regenerator is stably operated regardless of the inflow of power noise by preventing the malfunction of the CD driving circuit caused by the impulse (IMPLUSE) generated from the vehicle flowing into the power line in advance. The present invention relates to a method of preventing malfunction of a CD player, and in the present invention, when it is detected that the second transfer provided from the second voltage generator is lower than a lower limit voltage of the rated voltage, the low voltage state is maintained. If the low voltage holding time is shorter than the set time by checking the time, it is determined that the second voltage falls undesirably due to the impulse of the negative electrode, and passes without resetting the CD driver, and the low voltage holding time is longer than the set time. If it is long, it is judged that it is caused by external reset selection, By resetting the CD drive, the CD drive unit is normally operated, and the CD drive unit is reset by the power supply noise during playback of the first few songs of the CD. This will stabilize the operation of the CD player.

Description

How to prevent malfunction of CD player

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of preventing malfunction of a CD player. In particular, a CD driving circuit caused by an impulse (IMPLUSE) of a cathode generated in a vehicle is introduced into a power line is reset. By preventing the malfunction in advance, the present invention relates to a method of preventing a malfunction of a CD player which enables the CD player to be stably operated regardless of the inflow of power noise.

FIG. 1 is a schematic circuit diagram of a conventional CD player. Referring to FIG. 1, a conventional CD player generates a first voltage using a voltage provided from a battery 11 to generate a first voltage (eg, 8V). A second voltage generator 13 for generating a second voltage (eg, 5V) using the voltage supplied from the battery 11, and the first and second voltage generators 12 and 13; And a CD driver 14 for driving the CD regenerator to receive the voltage from the CD and to reproduce the CD. The voltage from the second voltage generator 13 is less than the lower limit voltage of the rated voltage. A microcomputer 15 for resetting the DSP (Digital Signal Processor) in the CD driver 14 is detected by detecting the case where the voltage is lowered, that is, when the second voltage is not supplied by the reset selection from the outside.

In the conventional CD player configured as described above, the second voltage generator 13 provides a second voltage of approximately 5V to the CD driver 14 as described above so that the CD driver 14 performs the corresponding function. If the impulse of the negative electrode flows into the power line output from the second voltage generator 13, the impulse number of the negative electrode affects the second voltage and thus from the second voltage generator 13. The voltage provided to the CD driver 14 drops below the lower limit voltage of the rated voltage for a predetermined time, and the microcomputer 15 detects that the second voltage falls below the lower limit voltage of the rated voltage so that the CD driver 14 Will reset the DSP.

However, when the second voltage is lower than the lower limit voltage of the rated voltage due to the impulse of the cathode, the DSP of the CD driver is reset even though it is caused by noise of the power line and not by normal reset selection. This causes the CD driver's DSP to be reset by the power supply noise generated during a short time, and the CD drive's internal DSP performs the signal processing function for CD playback from the beginning. This undesirably had a problem starting from the beginning.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and therefore, an object of the present invention is to prevent a malfunction in which a CD driving circuit caused by the impulse (IMPLUSE) of a cathode generated in a vehicle is introduced into a power line is reset. The present invention provides a method of preventing a malfunction of a CD regenerator which enables the CD regenerator to be stably operated regardless of the inflow of power noise.

1 is a schematic circuit diagram of a conventional CD player.

2 is a circuit diagram of a CD player for carrying out the present invention.

3 is a flowchart showing a method of preventing malfunction of the CD player according to the present invention.

Explanation of symbols on the main parts of the drawings

11 battery 12 first voltage generator

13 second voltage generator 14 CD drive unit

23: voltage detector 25: microcomputer

As a technical means for achieving the above object of the present invention, the method of the present invention comprises a first step of receiving a detection voltage from the voltage detection unit; A second step of determining whether the detected voltage input in the first step is lower than a lower limit voltage of a preset rated voltage and proceeding to the first step if the detection voltage is not low (high); A third step of turning on the internal timer when the detected voltage is lower than the lower limit voltage of the rated voltage in the second step; Counting time according to the operation of the timer; A fifth step of determining whether the time counted in the fourth step has elapsed a preset time; A sixth step of receiving the detected voltage from the voltage detector again when the set time has not elapsed in the fifth step; A seventh step of determining whether the detected voltage input in the sixth step is lower than a lower limit voltage of a preset rated voltage and proceeding to the fourth step if the detection voltage is low; An eighth step of controlling to reset the CD driver if the set time has elapsed in the fifth step; And a ninth step of returning to the first step after turning off the internal timer and after the eighth step if the detection voltage is not lower than the lower limit voltage of the rated voltage in the seventh step.

Hereinafter, a configuration of an apparatus for performing a malfunction preventing method of a CD player according to the present invention will be described with reference to the accompanying drawings. In the drawings referred to in the present invention, components having substantially the same configuration and function will use the same reference numerals.

FIG. 2 is a circuit diagram of a CD player for carrying out the present invention. Referring to FIG. 2, a circuit diagram of a CD player for carrying out the present invention uses a voltage provided from the battery 11 to determine a first voltage ( For example, the first voltage generator 12 for generating 8V, the second voltage generator 13 for generating a second voltage (eg, 5V) using the voltage provided from the battery 11, and And a CD driver 14 for driving the CD regenerator to receive the voltage from the first and second voltage generators 12 and 13 to regenerate the CD.

Then, the microcomputer for controlling the reset of the CD driver 14 based on the voltage detector 23 for detecting the output voltage from the second voltage generator 13 and the detected voltage from the voltage detector 23. It contains (25).

When the detection voltage from the microcomputer 25 becomes lower than the lower limit voltage of the rated voltage until a predetermined time elapses, that is, when the second voltage is not supplied by reset selection from the outside. Detects and resets the digital signal processor (DSP) in the CD driver 14, while the time when the detected voltage from the voltage detector 23 becomes lower than the lower limit voltage of the rated voltage is shorter than the preset time. The software is provided to control the CD drive unit 14 not to be reset by judging by the influence of noise on the line.

3 is a flowchart showing a method of preventing malfunction of the CD player according to the present invention.

Operation according to the present invention configured as described above will be described in detail below based on the accompanying drawings.

First, when the driver operates the CD player of the car audio, the microcomputer recognizes this and supplies power to circuit blocks associated with the CD player. In this way, the power is supplied from the battery 11 shown in FIG. A first voltage of approximately 8V is generated by the first voltage generator 12 using the power of the battery 11 and provided to the CD driver 14, and the battery ( Using the power of 11) generates a second voltage of approximately 5V to provide to the CD driver (14). In particular, the second voltage is a voltage required by the DSP in the CD driver 14.

In this way, when the first voltage and the second voltage required by the CD driver 14 are supplied, the software of the present invention embedded in the microcomputer 25 starts operation in the flow as shown in FIG.

Referring to FIG. 3, first, in the first step 31, the detection voltage is input from the voltage detector 23, which detects the first voltage output from the second voltage generator 13. The detection voltage is provided to the microcomputer 25, and the voltage detection unit 23 includes voltage division resistors R1 and R2, and the resistance ratio R2 / R1 is increased so that most of the second voltage is resistance. The detection voltage is almost equal to the second voltage by setting in advance so as to be applied to both ends of (R2).

In the second step 32, it is determined whether the detected voltage input in the first step 31 is lower than the lower limit voltage of the preset rated voltage. In this case, the lower limit voltage of the rated voltage is the lowest voltage at which the CD driver 14 can operate normally. For example, the lower limit voltage of the rated voltage is about 3V when the second voltage is about 5V. Therefore, it is determined whether the detection voltage is 3V or less.

In the third step 33, when the detected voltage is lower than the lower limit voltage of the rated voltage in the second step 32, the internal timer is turned on, which is used to check the time when the detected voltage is kept lower than the rated voltage. 25) The internal timer is running.

In the fourth step 34, the time is counted according to the operation of the timer turned on in the third step 33, which continues to count the time elapsed until the timer is turned off.

In the fifth step 35, it is determined whether the time counted in the fourth step 34 has elapsed a predetermined time, which will be described in detail below.

The predetermined time is the maximum time that the impulse of the negative electrode can be applied to the impulse of the negative electrode flowing into the power line and acting as the power noise, and this maximum time is approximately 20 ms according to the SAE test standard and the GM test standard. However, in the present invention, the set time is set to 30 ms in order to ensure more stability. Therefore, it is determined whether the time counted in the state where the detected voltage is lower than the lower limit voltage has passed the set time 30 ms.

In the sixth step 36, as in the first step 31, when the set time has not elapsed in the fifth step 35, the detection voltage is input again from the voltage detector 23, and the seventh step ( In step 37), it is determined whether the detected voltage input in the sixth step 36 is lower than the lower limit voltage of the preset rated voltage, and when it is low, the process proceeds to the fourth step 34.

In this way, while repeating the sixth step 36 in the fourth step 34, the time for which the detected voltage is kept lower than the lower limit voltage is counted, and whether the counted time is longer than the set time. The reason for this is to repeatedly determine whether or not the second voltage has dropped due to the impulse to be described below, or whether the second voltage has fallen due to the reset selection.

On the other hand, in the CD regenerator, the power supply is cut off by selecting the reset through the control unit of the car audio. At this time, the second voltage is kept lower than the lower limit voltage for a long time, but is applied to the power supply noise such as the impulse of the negative electrode. Therefore, the second voltage is kept lower than the lower limit voltage only for a very short time (about 20 ms).

In the eighth step 38, when the set time elapses in the fifth step 35, the DSP of the CD driver 14 is reset so that the detection voltage is lower than the lower limit voltage. Since the low state is maintained for more than the set time, the microcomputer 25 resets the DSP of the CD driving unit 14 by determining that the low state is not caused by the impulse of the cathode but by the reset selection from the outside. will be. When the DSP of the CD drive unit 14 is reset, since the CD drive unit 14 is initialized, the CD drive unit 14 reproduces the CD from the first song.

In the ninth steps 39 and 40, when the detected voltage is not lower than the lower limit voltage of the rated voltage in the seventh step 37, that is, when the detected voltage is higher than approximately 3 V, which is the lower limit voltage of the rated voltage, it normally recovers. After turning off the timer in operation, and after the eighth step 38, the process returns to the first step 31 to restart from the beginning of the present invention.

As described above, in the present invention, when it is detected that the second transfer provided from the second voltage generating unit is lower than the lower limit voltage of the rated voltage, the time for maintaining the low voltage state is checked to determine the low voltage holding time. If it is shorter than the set time, it is determined that the second voltage falls undesirably due to the impulse of the negative electrode and passes without resetting the CD driver, and if the low voltage holding time is longer than the set time, By resetting the CD drive unit, the CD drive unit is normally operated, and the CD drive unit is reset by the power supply noise during playback of the CD. Solves the problem of the CD player without affecting the power supply noise. It will be stabilized.

According to the present invention as described above, by preventing the malfunction caused by the CD drive circuit is reset in advance as the impulse (IMPLUSE) of the negative electrode generated in the vehicle flows into the power line, regardless of the inflow of power noise There is a special effect that allows the CD player to operate stably.

The above description is only a description of one embodiment of the present invention, the present invention is capable of various changes and modifications within the scope of the configuration.

Claims (1)

In the method of preventing malfunction of the CD player, A first step 31 of receiving a detection voltage from the voltage detector 23; The second step 32 proceeds to the first step 31 when it is not low (if high) by determining whether the detected voltage input in the first step 31 is lower than the lower limit voltage of the preset rated voltage. ); A third step 33 of turning on an internal timer when the detected voltage is lower than the lower limit voltage of the rated voltage in the second step 32; A fourth step 34 of counting time according to the operation of the timer; A fifth step (35) of determining whether the time counted in the fourth step (34) has elapsed a preset time; A sixth step 36 of receiving the detected voltage from the voltage detector 23 again when the set time has not elapsed in the fifth step 35; A seventh step 37 of proceeding to the fourth step 34 when it is determined whether the detected voltage input in the sixth step 36 is lower than a lower limit voltage of a preset rated voltage; An eighth step (38) of controlling the CD driving unit (14) to be reset when the set time has elapsed in the fifth step (35); In the seventh step 37, if the detected voltage is not lower than the lower limit voltage of the rated voltage, the ninth time is returned to the first step 31 after turning off the internal timer and after the eighth step 38. Step (39, 40); preventing the malfunction of the CD player, characterized in that consisting of.